The present invention relates to containers for cosmetic preparations and to cosmetic products incorporating such containers. The invention relates particularly but not exclusively to containers for facial colouring materials, such as mascara, lipgloss, lipstick, and the like. Such cases were originally made completely of metal. These cases had various draw-backs, notably:
internal corrosion by the cosmetic product PA1 high cost of materials and assembly PA1 difficulties in achieving adequate air tight and liquid-tight metal-to-metal joints PA1 metal fines and shred occasionally present in the cosmetic product PA1 expensive and difficult to color and to decorate.
Injection molded and blow molded plastic containers were subsequently introduced in order to resolve the above problems and are now widely used.
However the use of plastic containers has given rise to manufacturing problems. In particular, the material of the container has had to be carefully chosen according to the cosmetic preparation. For example, cosmetic preparations, such as make-up, mascara and lipgloss, which are water-based require a container made of polyolefin resin whereas other cosmetic products incorporating a hydrocarbon base require a PVC or other special resin container. The reason for this is that if such a PVC or other resin container is used for an aqueous cosmetic product or a polyolefin resin container is used for a hydrocarbon-based cosmetic product, then the vapor of the base is liable to permeate through the container, leading to drying and hardening of the product. Even if the optimum plastic is chosen for the particular cosmetic preparation used, eventually some of the base is liable to permeate through the container walls and accordingly the shelf life of the product is limited. Because PVC and polyolefin resins have different cooling characteristics, resulting in different degrees of shrinkage upon solidification and cooling during the molding process, different molds are required for making identically dimensioned containers from these materials, with the disadvantages of the attendant cost and inflexibility of the different molds.
Also, while the plastic containers can be made more economically than all-metal containers, they do not have the "quality" feel, weight and appearance of the latter.